Answer:
The answer is letter A.
Step-by-step explanation:
The amount that each company charges per hour on the pool is known, however the amount of hours they will be working is not, and is needed to distinguish which company is cheaper. Therefore, the number of hours is substitued by x and it is right next to the amount they charge for each hour. To find what each company charges, you must sum up what they charge and what they charge per hour, times the hours they will have to work on it( which is unknown and by x).
5(11x-5)=85
55x-25=85
+25 +25
55x=110
---- -----
55 55
x = 2
<h3>Answers:</h3>
1% of 300 is <u> 3 </u>
So 64% of 300 is <u> 192 </u>
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Further explanation:
To take 1% of 300, we just chop off the extra zeros. So that's how I got 3.
To go from 1% to 64%, that's a jump of "times 64". Meaning you multiply that '3' by 64 to get 64*3 = 192.
Notice that 192/300 = 0.64 = 64% to confirm the answer.
Answer:
The claim that the current work teams can build room additions quicker than the time allotted for by the contract has strong statistical evidence.
Step-by-step explanation:
We have to test the hypothesis to prove the claim that the work team can build room additions quicker than the time allotted for by the contract.
The null hypothesis is that the real time used is equal to the contract time. The alternative hypothesis is that the real time is less thant the allotted for by the contract.

The significance level, as a storng evidence is needed, is α=0.01.
The estimated standard deviation is:

As the standard deviation is estimated, we use the t-statistic with (n-1)=15 degrees of freedom.
For a significance level of 0.01, right-tailed test, the critical value of t is t=2.603.
Then, we calculate the t-value for this sample:

As the t-statistic lies in the rejection region, the null hypothesis is rejected. The claim that the current work teams can build room additions quicker than the time allotted for by the contract has strong statistical evidence.